The present disclosure generally relates to an apparatus and method for monitoring consumption of sewing thread by a stitch-forming machine and, more particularly, to an apparatus and method for providing a warning of an impending depletion of a supply of sewing thread. Even more particularly, the present disclosure generally relates to an apparatus and method for collecting data on the consumption of sewing thread by a stitch-forming machine.
In the sewing industry, it is often desirable to know the amount of thread being consumed by a stitch forming machine, such as a sewing machine, since the consumption of thread can be, for example, an indication of the quality of seams produced and the efficiency of a large scale sewing process, such as in a garment factory. It is also desirable to know when a supply of thread, e.g., a bobbin of thread, is about to run out, since running out of thread without warning while sewing is at the very least an inconvenience. Furthermore, the unexpected loss of thread while sewing a seam can require the removal and replacement of the unfinished seam, and could even result in a defectively sewn product.
Some previously existing devices for measuring thread consumption included mechanical measuring devices and a meter or other display for measuring and displaying the total amount of thread consumed. However, one drawback associated with such devices is that they do not provide an alarm for warning of an impending depletion of the thread supply. Preferably, an apparatus for measuring thread consumption will provide an alarm for warning of an impending depletion of the thread supply.
A number of devices for measuring thread consumption do include a low thread supply alarm. U.S. Pat. No. 5,339,758, for example, provides such a device. Many of these devices, however, such as that disclosed in U.S. Pat. No. 5,339,758, measure thread consumption by monitoring the rotation of the bobbin itself. However, quite a few types of sewing machines draw thread from bobbins without actual rotation of the bobbins. Accordingly, an apparatus for measuring thread consumption will preferably measure thread consumption independently of the rotation of the bobbin, such that it can be used with sewing machines that do not utilize rotating bobbins.
It is also desirable to provide a thread consumption monitoring apparatus that allows a user to enter an initial amount of thread on a bobbin and a minimum allowable amount of thread to remain on the bobbin. Preferably, the apparatus will store the overall total amount of thread consumed and allow a user to access that information. In addition, the apparatus will preferably store the total number of bobbins emptied by the sewing machine and allow a user to access that information.
Furthermore, it is desirable to provide an apparatus for monitoring thread consumption that allows a user to select between a count-up mode, wherein the displayed thread amount begins at zero and the thread consumption progresses up towards the initial amount of thread, and a count-down mode, wherein the displayed thread consumption begins at the initial amount of thread and progresses down towards zero. Furthermore, the apparatus will preferably allow a user to pause the consumption monitoring, in the event, for example, of thread breakage.